/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package zipkin2.server.internal;

import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.boot.context.event.ApplicationReadyEvent;
import org.springframework.context.ApplicationEvent;
import org.springframework.context.ApplicationListener;
import zipkin2.Component;

/** Makes sure all zipkin components end up in the /health endpoint. */
// This is an application listener to ensure the graph is fully constructed before doing health
public final class RegisterZipkinHealthIndicators implements ApplicationListener {

  @Override
  public void onApplicationEvent(ApplicationEvent event) {
    if (!(event instanceof ApplicationReadyEvent)) return;
    ConfigurableListableBeanFactory beanFactory =
        ((ApplicationReadyEvent) event).getApplicationContext().getBeanFactory();
    ZipkinHealthIndicator healthIndicator = beanFactory.getBean(ZipkinHealthIndicator.class);
    for (Component component : beanFactory.getBeansOfType(Component.class).values()) {
      healthIndicator.addComponent(component);
    }
  }
}
